Wyniki wyszukiwania - BazTech

1

Synthesis and characterization of titanium carbide particulate reinforced AA6082 aluminium alloy composites via friction stir processing

Thangarasu A., Murugan N., Dinaharan I., Vijay S. J.

Archives of Civil and Mechanical Engineering

|

2015

|

Vol. 15, no. 2

324--334

EN

Friction stir processing (FSP) has evolved as a novel solid state technique to fabricate aluminium matrix composites (AMCs) in the recent years. FSP technique was applied to synthesis AA6082/TiC AMCs in order to analyze the effect of TiC particles, its volume fraction on the microstructure, mechanical and the sliding wear behaviour. A single pass FSP was carried out using a tool with 1200 rpm rotational speed, whose travel speed of 60 mm/min and an axial force of 10 kN to produce the composite. AMCs with five different volume fractions (0, 6, 12, 18 and 24 vol.%) were synthesized. The microstructure of the AA6082/TiC AMCs was studied using optical and scanning electron microscopy. The microhardness and ultimate tensile strength (UTS) were measured and the sliding wear behaviour was evaluated using a pin-on-disc apparatus. Thus the results revealed that the TiC particles significantly influenced the area of the composite, dispersion, grain size of matrix, microhardness, UTS and sliding wear behaviour of the AA6082/TiC AMCs. With this the effect of TiC particles on fracture surface and worn surface is also reported in this paper.

2

Influence of tool traverse speed on the characteristics of dissimilar friction stir welded aluminium alloy, AA5052 and HSLA steel joints

Ramachandran K. K., Murugan N., Shashi Kumar S.

Archives of Civil and Mechanical Engineering

|

2015

|

Vol. 15, no. 4

822--830

EN

In the present work 3 mm thick aluminium alloy AA5052 and HSLA steel were successfully butt joined using friction stir welding (FSW) technique. The FSW trials were carried out by varying the tool traverse speed while keeping the other parameters constant. The joint characteristics such as ultimate tensile strength (UTS), microhardness, microstructure at the joint interface and fracture surface of fractured tensile specimens were investigated. SEM and EDS analysis suggest that in all cases intermetallic compound (IMC) layer is formed at the joint interface and its thickness is critical in the tensile strength of the joint. For a given tool rotational speed, axial load and tool tilt angle, the tool traverse speed has significant influence on the thickness of IMC layer formed and hence on the joint strength. The highest joint strength of about 91% of UTS of the base aluminium alloy is obtained at tool traverse speed of 45 mm/min and the UTS follow approximately a centre peak type variation against tool traverse speed.

3

Fabrication and Characterization of CU/B4 C Surface Dispersion Strengthened Composite using Friction Stir Processing

Sathiskumar R., Murugan N., Dinaharan I., Vijay S. J.

Archives of Metallurgy and Materials

|

2014

|

Vol. 59, iss. 1

83--87

EN

Friction stir processing has evolved as a novel method to fabricate surface metal matrix composites. The feasibility to make B4 C particulate reinforced copper surface matrix composite is detailed in this paper. The B4 C powders were compacted into a groove of width 0.5 mm and depth 5 mm on a 9.5 mm thick copper plate. A tool made of high carbon high chromium steel; oil hardened to 63 HRC, having cylindrical profile was used in this study. A single pass friction stir processing was carried out using a tool rotational speed of 1500 rpm, processing speed of 40 mm/min and axial force of 10 kN. A defect free interface between the matrix and the composite layer was achieved. The optical and scanning electron micrographs revealed a homogeneous distribution of B4 C particles which were well bonded with the matrix. The hardness of the friction stir processed zone increased by 26% higher to that of the matrix material.

PL

Zgrzewanie tarciowe ewoluowało jako nowa metoda wytwarzania kompozytów powierzchniowych z osnową metaliczną. W pracy szczegółowo opisano możliwość wytworzenia kompozytu na powierzchni miedzi zbrojonego cząstkami B4 C. Proszki B4 C sprasowano w rowku o szerokości 0,5 mm i głębokści 5 mm wykonanym na blasze miedzianej o grubości 9,5 mm. Do wytworzenia kompozytu użyto narzędzia o profilu cylindrycznym, z wysokowęglowej stali o wysokiej zawartości chromu, hartowanego w oleju do 63 HRC. W jednym przebiegu obróbki zgrzewanie przeprowadzono przy prędkości obrotowej narzędzia 1500 obr/min. szybkości przesuwu 40 mm/min i osiowej siły 10 kN. Osiągnięto cel w postaci pozbawionego wad połączenia pomiędzy matrycą i warstwą kompozytu. Mikrofotografie optyczne i ze skaningowej mikroskopii elektronowej wykazały jednorodną dystrybucję cząstek B-C, które były dobrze połączone z matrycą. Twardość strefy zgrzewnej tarciowo wzrosła o 26% w stosunku do materiału matrycy.

4

Modelling, analysis and optimisation of weld bead parameters of nickel based overlay deposited by plasma transferred arc surfacing

Siva K., Murugan N., Raghupathy V.P.

Archives of Computational Materials Science and Surface Engineering

|

2009

|

Vol. 1, nr 3

174-182

EN

Purpose: Plasma Transferred Arc surfacing is increasingly used in applications where enhancement of wear, corrosion and heat resistance of materials surface is required. The shape of weld bead geometry affected by the PTA Welding process parameters is an indication of the quality of the weld. In the paper the modelling, analysis and optimization of weld bead parameters of nickel based overlay deposited by plasma transferred arc surfacing are made. Design/methodology/approach: The experiments were conducted based on a five factor, five level central composite rotatable design and a mathematical model was developed using multiple regression technique. The direct and interaction effects of input process parameters of PTA Hardfacing on weld bead geometry are discussed. Finally, Microsoft Excel Solver has been used to optimize the process parameter with a view to economize the powder and achieve the desirable bead dimensions. Findings: Penetration, dilution and total area are increased when the welding current is increased but reinforcement marginally increases and then decreases. Penetration, weld width, dilution and total area decrease when travel speed is increased. Reinforcement increases slightly and then decreases. Practical implications: The developed mathematical models can be used to predict the dimensions of the weld bead and dilution. Originality/value: This paper highlights the development of a mathematical model correlating various process parameters to weld bead geometry in PTA hardfacing of Colmonoy 5, a Nickel based alloy over Stainless steel 316 L plates.